Method of making pressure tanks



Feb. 9, 1943. e. E. BULLOCK METHOD OF MAKING PRESSURE TANKS Filed May 8, 1940 Q A TT I ORNE Patented Feb. 9, 1943 UNITED STATES PATENT OFFICE METHOD OF MAKING PRESSURE TANKS Giles E. Bullock, Rochester, N. Y. Application May 8, 1940, Serial No. 334,017 1 Claim. (Cl. 29-1483) This invention relates to the manufacture of pressure tanks made up of thin sheet metal and has for its principal object to provide a novel method and construction which permits a simultaneous galvanizing of the entire inside and outside surface of the tank and at the same time provides a novel closure seat around the open end thereof.

This and other objects and attendant advantages of the invention will become more readily apparent from the detailed description thereof which follows, reference being had to the accompanying drawing in which the figure shows a longitudinal sectional view of a tank made in accordance with my invention.

As illustrated in this figure the tank is built up of a cylinder I, a head 2 in the bottom of the cylinder and a head 3 in the top of the cylinder. The bottom head 2 telescopingly engages into the inside of the cylinder and is electrically welded in place therein. The head 3 at the top of the cylinder telescopingly engages over the outside thereof and is electrically welded in place thereon.

Centrally of the head 3 is provided the filling opening I and surrounding this opening is formed the closure seat 5. The latter is formed in the a shape of an inverted channel so as to provide a restricted, uniform seating surface raised above the head 3 with a hollow center of substantially semi-cylindrical cross section.

In the bottom head of the tank is provided a small vent opening which is adapted to be closed by a suitable plug 1. Thisopening provides for the escape of air from within the tank when the tank is immersed in the galvanizing bath in the coating thereof. In the process of galvanizing, the tank is submerged in a substantially inverted position in order to have the galvanizing composition flow thru the large opening into the inside of the tank to simultaneously place a galvanize coating 8 on the inside and the outside of the tank. In the immersion the air trapped in the tank is forced out of the vent opening 8 in the bottom head so that the galvanizing composition entering the tank can quickly and completely replace the air and contact any part of the surface within the tank for the efficient coating thereof.

In withdrawing the tank from the galvanizing bath, a quantity of the galvanizing composition is scooped up by the inverted channel which surround the filling opening 4 so that the channel remains practically filled therewith. In this way the galvanizing composition not only provides a non-corrosive coating both inside and out of the closure seat, but simultaneously reinforces the seat by forming a solid core 9 in the otherwise hollow seat.

This novel method of making and processing a tank thus produce an extremely strong and inexpensively constructed non-corrosive tank made up of sheet metal and provides this tank with a raised closure seat which is formed integrally around the filling opening in the head and simultaneously galvanized with the tank in such a manner that the galvanizing not only completely coats its surface but also reinforces the closure seat with a core which fills the hollow portion of the seat and prevents accumulation of foreign matter around the filling opening at the bottom of the seat.

I claim:

, The method of making a metallic receptacle which consists in forming from sheet metal a cylinder and a head for each end of the cylinder, providing a small opening in one of the heads and a large opening in the other of the heads, providing a closure seat around the large opening of one of the heads by raising the marginal portion of said head around its large opening in the form of an inverted channel, tele-' scopingly connecting the heads to the cylinder and then immersing the entire receptacle in a galvanizing oath so as to cause the galvanizing material to enter the large opening in one of said heads and displace the air thru the small opening in the other of said heads and thus coat its entire area inside and out to fasten and seal the heads to the cylinder and simultaneously provide a core in the hollow portion of the closure seat.

GILES E. BULLOCK. 

